Why European SMBs Are Replacing Microsoft 365 with Nextcloud and OnlyOffice

For years, Microsoft 365 was the unquestioned default for European businesses. It was convenient, ubiquitous and deeply integrated. But a growing number of small and mid-sized companies across the continent are reconsidering, and a credible open alternative — built around Nextcloud and OnlyOffice — has matured enough to make switching realistic.

This is not anti-Microsoft ideology. It is a sober reassessment of cost, control and compliance by businesses that have grown uneasy about routing their entire operational life through a single American platform whose pricing and terms they do not control.

What is driving the switch

Three pressures recur in conversations with European SMBs. The first is cost: per-seat licensing climbs relentlessly, and for a 50-person company the annual bill is substantial and ever-rising. The second is data residency: leaders are increasingly uncomfortable that their documents, email and chat sit on infrastructure subject to foreign data-access laws. The third is lock-in fatigue — the sense of being trapped in an ecosystem that is hard and expensive to leave.

• Predictable cost: self-hosted or EU-hosted suites replace per-seat creep with capacity-based pricing
• Data residency: documents and email stay on EU infrastructure under EU jurisdiction
• Control: open formats and open source mean no surprise deprecations or forced migrations
• Compliance: a cleaner GDPR story with no transatlantic data transfers to justify

The open stack that replaces it

The modern open office stack maps surprisingly cleanly onto Microsoft 365. Nextcloud provides file sync, sharing and a collaboration hub equivalent to OneDrive and SharePoint. OnlyOffice or Collabora deliver real-time co-editing of documents, spreadsheets and presentations with strong Microsoft-format compatibility. Email moves to a provider such as mailbox.org or Infomaniak, and chat and calls to Element or Jitsi.

Compatibility: the honest answer

The most common objection is document compatibility, and it deserves a straight answer. For the vast majority of everyday documents — reports, proposals, standard spreadsheets, slide decks — OnlyOffice and Collabora handle Microsoft formats well, preserving layout and formatting reliably. Where friction remains is at the extremes: spreadsheets with intricate macros, or documents built around Microsoft-specific features.

The pragmatic approach is to identify those edge cases up front. Most organisations find that a small minority of power-user files need special handling, while everyone else transitions smoothly. Knowing which is which before you migrate prevents nasty surprises.

A realistic migration playbook

Successful migrations are gradual, not big-bang. A sensible sequence:

1. Audit how you actually use Microsoft 365 — which features are essential versus habitual
2. Choose your hosting: self-managed for maximum control, or a managed EU provider for less overhead
3. Pilot with one willing team and gather honest feedback
4. Migrate files in batches, starting with active projects and archiving the rest
5. Train users — the interface differs, and a little guidance prevents frustration
6. Run both systems in parallel briefly, then decommission the old licences

What it costs — and saves

The economics vary with the hosting choice. Self-hosting trades licence fees for infrastructure and a modest amount of administration, which suits organisations with some technical capacity. Managed EU hosting costs more than self-hosting but typically still undercuts per-seat licensing at scale, while removing the operational burden.

Beyond the headline savings, businesses report a less tangible benefit: control. Owning your collaboration platform means no forced upgrades, no surprise price increases and no dependence on a vendor’s roadmap. For many, that resilience is worth as much as the cost reduction.

Migrating email and calendar

Files are usually the easy part; email and calendar are where migrations get nervous, because they are mission-critical and unforgiving of downtime. The good news is that email is built on open standards (IMAP, SMTP, CalDAV) that make moving between providers far more straightforward than moving, say, a proprietary database. European hosts such as mailbox.org, Infomaniak and Mailfence provide migration tooling that copies existing mailboxes across with folders and history intact.

The critical sequencing point is the MX record cutover — the moment incoming mail starts flowing to the new provider. Done carefully, with mailboxes pre-synced and a short overlap window, the switch is invisible to users and to people emailing them. Done carelessly, it bounces mail. This is the one step that rewards meticulous planning and a maintenance window, ideally over a weekend.

Calendars and shared resources need attention too: recurring meetings, shared room calendars and delegated access all have to be recreated or migrated. None of it is hard, but it is detailed, and skipping the inventory stage is how organisations discover three weeks later that the finance team’s shared calendar never came across.

Change management: the human side

The biggest risk in any office-suite migration is not technical but human. People are fluent in the tools they use daily, and even a superior alternative feels worse at first simply because it is unfamiliar. Underestimating this is the most common cause of migrations stalling or being reversed under a wave of complaints.

The antidote is communication and support. Explain why the change is happening — cost, control, compliance — so people understand it is a deliberate strategic choice rather than IT inflicting pain for its own sake. Provide short, task-focused guides for the handful of things people do most often. Identify enthusiastic early adopters in each team who can help their colleagues. And gather feedback quickly so genuine problems are fixed before they harden into resentment.

Organisations that invest in the human side report that the grumbling subsides within a few weeks as new habits form, and that users often come to prefer the cleaner, less cluttered open tools. The technology was never really the obstacle; the transition was.

Conclusion

Replacing Microsoft 365 is no longer the heroic undertaking it once was. The open European stack has matured into a genuine alternative that delivers the collaboration features SMBs actually use, on infrastructure they control, with a cleaner compliance story and lower long-term costs.

The key is to approach it as a managed transition rather than a leap of faith. Pilot first, migrate in stages, support your people, and the switch becomes not just feasible but, for a growing number of European businesses, obviously worthwhile.